Question

policies
current attempt in progress
a mixture of ethyl alcohol (molecular mass = 46.1 u) and water (molecular mass = 18.0 u) contains one mole of molecules. the mixture contains 13.1 g of ethyl alcohol. what mass m of water does it contain?
m = number
units
attempts: 0 of 5 used

Explanation:

Step1: Calculate moles of ethyl alcohol

Molar mass of ethyl alcohol ($M_{ethanol}$) = 46.1 g/mol, mass of ethyl alcohol ($m_{ethanol}$) = 13.1 g. Moles of ethyl alcohol ($n_{ethanol}$) = $\frac{m_{ethanol}}{M_{ethanol}}$ = $\frac{13.1\ g}{46.1\ g/mol}$ ≈ 0.284 mol.

Step2: Calculate moles of water

Total moles of molecules = 1 mol. So moles of water ($n_{water}$) = 1 mol - $n_{ethanol}$ = 1 - 0.284 = 0.716 mol.

Step3: Calculate mass of water

Molar mass of water ($M_{water}$) = 18.0 g/mol. Mass of water ($m_{water}$) = $n_{water} \times M_{water}$ = 0.716 mol × 18.0 g/mol ≈ 12.9 g.

Answer:

12.9 (Units: grams)